CW buttons - 7th Mass?

[J Norquist]

I am a reenactor. My uniform is currently standard issue Union infantry (private). I have a distant relative that was in the 7th Massachusetts infantry and wounded in the second battle for Marye's Heights, Fredericksburg. I would like to replace my standard issue coat button with buttons for the 7th Massachusetts. Should the buttons be the 'hand and sabre' design or the 'coat of arms'? Where can I get reproductions? Original buttons seem to be about $20 each. That is outside my budget.
Thanks
J Norquist

 

[J Norquist]

Also, what were the brass insignias for the Kepi? My relative was in 'H Co, 7th Mass. (Edward F. Hall) I have the standard insignia for infantry. Is the numeral '7' and an 'H' historically correct for the kepi? What is the placement for the '7' and an 'H'?
Thanks
J Norquist