When I am looking at Contenders, here is what catches my eye:
frame and one barrel : 10" or 14" with stock sights....$250 or close there abouts.
Barrels - Stock.... $150 and less
Barrels - bare.......$140 and less
Barrels with scopes......$150 - $200 unless top end Leupold, Burris, or similar scope.
Custom or aftermarket barrels with dies and brass $175 - $200 and up depending on the extras.
Any custom or aftermarket barrel selling for near value is suspicious. Why would someone sell a new XYZ barrel for $20 less than new....unless it wouldn't shoot, or dies cost $100 or more, or ....or......I just order a new one if I want one and avoid the endless negative possibilities.
Any custom or aftermarket barrel selling with dies, brass, load information are open to discussion and negotiation. I have several plain jane barrels that I have purchased for $300+ because of what they were and the info they came with. Two barrels of this category immediately come to my mind: A 30 Bower Alaskan barrel, plain (no sights or scope base), with Bower's load info and dies. A 7MM Bower, plain, with dies, Bower load info, and photos of previous owner shooting same barrel with Don Bower. I paid premium $s for these barrel because I know who made them, received the dies, and know they would shoot. Worth every dime I paid.
If I were you, I would NOT sell as a set. I would sell frame separately from each of your barrels with any specialty dies with them as an extra. If someone wants one of your barrels real bad, offer them the frame as a package for about $20 less.
Your three barrels, IMHO, are worth: 22 $200, 7x30 $225-250, 358 JDJ $250-300 if you include dies and brass. If you pull off the scopes and bases and sell everything seperately, you could get a little bit more.
Of what you have there, I personally would be interested in the 3 and 4 ring bases. (I am NOT offering or in no way attempting a solicitation here....EXAMPLE ONLY!!) The rest I would re-trade or re-sell. This is how a lot of buyers are right now. Someone may buy a barrel just to get the scope and then re-sell barrel and base/rings.
You will get less selling all as a package. The more you break down the pieces, the more $$ you are likely to get.
Just my $.02....again, not an offer or solicitation of a sale.
Steve