Confederate Chaplains are a misunderstood impression. For example I have a friend h**lbent on having his chaplain rank in the SCV and is adamant he's an officer and wears rank when there's no real evidence of this in the CW. (He's a great guy, great friend, I just have sore eyes from rolling them so much when the subject turns to Confederate Chaplains.)
Confederate Chaplains were usually sent along with a company or regiment by the congregation of his and his unit's hometown and to my knowledge, never had any real military authority. The pay they received from the Confederate government was the same as for a lieutenant, and outside of the faith they really just helped the doctors in field hospitals, or at least that's what I would look for them to be doing most of the time. They were there to serve as a representative of Lord, not fight battles.
While some examples of military uniforms for Chaplains exist, one must remember that like officers they were more likely to have pay for their own uniform to be made by a tailor in some town or city, not issued to them the CS military. This is why with originals there is wide variances in the survivors as from the examples I know, their all different, but they do have one thing in common. They're all in good to very good shape. This to me is an indicator that they were not worn very much in the field, or at the very least just used as a form of dress uniform. So yeah one should bear that in mind when building a CS Chaplain's impression. And no as a man of the cloth I find it highly doubtful they carried weapons, Federal Chaplains weren't known for it, I see no reason why Confederate ones would be either. They're job was to do the Lords work in a situation that was H**l on Earth, joining in on the warfare would go against they're heavenly duties.
So keeping that in mind, I would recommend the impression consist of:
1. Plain civilian trousers, black being the most likely, probably keeping to materials like satinette, or wool broadcloth.
(I'm not sure jeans would have been used by a man of the cloth, that was more of poor man's material, but hey it's possible)
2. A plain frock coat, or at least civilian sack coat, same rules for colors and materials as above.
("Class A" type folks go with matching, and in the 19th Century more often than not preachers were gonna be VERY fastidious about they're clothing wherever possible. They were supposed to representing the Lord.)
3. The religious preacher collar thing commonly worn back then by preachers.
(I have no idea about it, but I'd bet on Sunday at services it'd be worn, everyday probably not.)
4. Plain everyday brogans, most likely black wherever possible.
5. A period correct Bible.
Those are my educated guesses at the minimum for a proper Confederate Chaplain impression, but I would say with no doubt in my mind weapons, and military officers rank were the very rare exception, and highly unlikely, not the rule. Even the most h**lfire and brimstone preacher would be hesitant to walk around armed to the teeth, and IF armed, it would more than likely be a small pocket pistol or revolver, no holstered weapon.
Sorry if I seem hardnosed on the subject, but Confederate Chaplain impressions are HEAVILY abused. Many folks go for that impression to be an officer, and strut around like they're a General. But they weren't, they were men of the Lord serving in the military to be the soldiers rock, or rather man to look up too, or lean on when they were at their worst. Folks like to always point out to me that military has chaplains who are military officers, but that is a modern concept, and one that didn't exist back in the 1860's And a lot of folks flat out refuse to believe that line of thought because they want to be an officer in reenactments without going through the process of earning it.
(On a side note the same thing happens with field surgeon impressions, but that's a whole other subject.)
But hey if your hearts in the right place go for it, good luck and God bless! The hobby needs good chaplain impressions.