Louis is an expert on this so I will defer to his opinion but it's very hard to find these. I think a lot has to do with networking, being in the right place in the right time. There are certain collectors who are good at ferreting these out. However, I'm not one of them. I managed to find one on my own but I owe that more to luck than anything else. In sum, I agree with Pierre that there is no secondary market out there for these planes. If there is, please give me the number so I can get in the door.
Thus, I don't think it will affect the existing market and I'm not too sure the sellers would mind either. I'm sure the buyers wouldn't be upset either. You're not usually buying these with an eye on resale as you might with some figures or tanks.
On another point, binder, seconded by Carlos, was worried that producing more warbirds, might distract Andy's attention from making tanks, etc. However, I didn't see this point being raised when Andy said he was re-starting the Alamo or starting the Crusader line. It hasn't apparently stopped him from planning future WW 2 releases and, moreover, I don't think he's concerned. So, I don't think those particular objections have a lot of merit.