Some of those bows will bring big bucks, some are mideocre.
The rule of thumb is that they are worth what someone will pay...no more, no less. the only way to really know is to put hem up for auction on e8ay. The bidders will set the value.
Of course that does not say that he is ready to sell them right now, so that may not be a good way to find out.
Some others here may step in and give their opinion as to what some of these are worth to them.
Now in my ignorance, I was not aware that there was aa Signature "A" handle. I thought they were all "B" risers in the series. That bow should bring big bucks. I know some of the "B" risers Signatures have gone for as much as $5000.00, possibly more. In my opinion, an "A" riser would be less common and possibly be worth more. In any case, the value will be effected by the economy, the condition, if it is signed by Papa Bear, and other factors.
You can go to e8ay and search for these individual items under arcehry in the compleated items catagory and see what like items have sold for over the past 60 days, although I am sure you will not find some of those rare items.
Now if he wants to sell me the Signature A handle in the case, I will give him $100.00 for it...hey, I took a shot.