G'day Alan, that is a really really tough question mate! In, the short time I've been collecting I haven't seen one full decent one for sale. So the problem with price isn't just subjective it's also the lack of a selling market. It comes down to finding one, getting the owner to sell it, negotiating with the seller on price and then what you're willing to spend. I did comment previously that if I could justify the $$$ I'd spend $500 for just a basic runner without catcher, but I'd definitely have to be well off enough to consider it, and I'm not!
So good luck mate, I mean that, if you want one bad enough you will find one and then it's really what you are willing to fork out! But remember, you don't have to tell anyone what you pay either! It will be yours and your choice what you tell people or don't!!!