Maybe I should go rummage under my workbench. I am not sure as to how many receivers I have in various stages of assembly are piling up under there. As I play working on restoring my projects, take off parts get tossed into the junk drawer until on day, bingo. I have enough bits and pieces to assemble a working sporter rifle.
If you are handy and have a bench and tools, no, don't spend a lot of money on it, just gather parts as you go. The big part of this hobby for me is finding and horse trading for the missing parts. I got a bolt I would trade for something. Somebody probably has a set of sporter wood that they don't need anymore that they would let go cheap. If you are patient the project won't have to cost a great amount of money. I have built rifles starting with a lot less.
I say go for it. You need to find somebody with a barrel vise and an action wrench, it would take but a few minutes to screw that barrel in. The tooling and gauges to do it yourself would run you about $300, so not really viable if you were to do just the one barrel.
If you want to learn, it'll be a great winter project. You will make mistakes, but that is part of practicing a craft, but you wont be hurting anything valuable or collectable.
If you do everything yourself it will be cheap. If you have to pay someone to do everything for you, the cost will be similar to building a custom safari rifle.
If you are not going to do anything with them, ya, $40-50 would be about right for a price tag to sell them.