The entire balance seems backwards.
I don't mind restoration being expensive - it should be.
But ships are comparatively too cheap. Naturally, if you increase ship prices across the board, then you'll also have to increase bounty prices.
Getting high-level faction ships should be possible in only 3 ways:
1. buying with commission
2. salvaging (but the original owner faction might require some bribing to overlook it)
3. Black market - but with a big reputation penalty. You cannot hide that you do not have a government contract of purchase, nor can you hide that what you are driving is a Conquest that was reported lost two weeks ago.
If the US was to loose a destroyer and if I were to salvage it, you can bet that the US military wouldn't just ignore me as I come to port. They might take it from me by force, or hey might agree to allow me to keep it (for a price)
Non-civilian Capital ships don't usually show up in black markets.
I see them all the time. Perhaps some of the mods require some tag to make them non-sellable or something, but I seem to recall seeing vanilla capitals on OPEN MARKET.