If you have the opportunity to get an 1863 Springfield, consider it carefully. The advice you've been given earlier is good, ESPECIALLY the link about if my house burned down tonight.
Here's why I say consider it carefully. The unit I am in did not have 1863 Springfields for the time I am representing in my impression. In fact, as far as I can tell from the limited research I've done and from talking to other members in my reenactment unit, the 5th Minnesota did not have 1863 Springfields at all. My impression is based on Company D's time at Fort Abercrombie, Dakota Territory, during the 1862 Sioux Uprising. The company had 1842 Springfields at that time; fortunately, I was able to acquire one at a reasonable price. (Since I live 35 miles away from Fort Abercrombie and make presentations there, it's a nice fit for me.) The 5th carried these muskets until after Vicksburg, when they were exchanged for .58 cal rifles.
If you end up with a unit that used 1863 Springfields, and you get this gun, good, it all worked out for you. Your impression will be a better one for having the correct weapon. If the unit you join did not have these weapons, then you have a choice to make. Over time, you may want to keep the 1863 and use it to trade for another weapon. You can keep it and use it as a loaner piece to other newcomers until they can obtain the right weapon. You may want to keep it and use it to develop a collection of Civil War firearms. Or you may want to develop other impressions the longer you stay in the hobby or if you move to a new home in another area, joining a different unit. It all depends on how accurate you want your impression to be, and how much you can afford to spend.
I didn't buy anything until I'd found this unit and did some researching on what I could do and could afford over time. Best advice I've been given in this hobby, and I've only been doing this for a little over a year. I don't have a complete kit yet, but that will come over time. If I am able to at some point in the future, I would like to get the rifle the 5th was issued after Vicksburg. But that is a long way off.
Welcome to the hobby and enjoy it!