Here is my newbie two-cents;
In general, I would think a good used saddle. However what “good” means is something to consider.
I’ve been looking at anything used from Voltaire, Tad Coffin, Butet, Devoucoux and other really nice brands. Also have looked at others including the Bates Collegiate, Toulose, and even Wintec. Here is what I think;
A saddle that is too old is going to need re-flocking, padding, etc. and will have dried leather parts, and stiffer flaps, etc. Not to mention the look.
I would look for something not “too used”, so you have some quality/safety. The looks of things matter to me personally, so not too scuffed up, etc. appeals more to me. I know your guy is coming out of retirement, but still, you both deserve a nice ride!
I agree that the really cheaper new saddles do not seem to be very good at all, and I’m thinking I need to be near or over $2000 to get into something I would like for a new saddle. (or, then spend that much on a high quality, less-used saddle) To find the perfect CWD or Devoucoux (sp), at a fair price, it would be “high” for used, but not new pricing. https://www.devoucoux.com/us/en/used-saddles
This is like cars, you drive it off the lot, and it’s still perfect, just 20% devalued. Another 10K miles and you save an additional 10%, but thereafter, you will have a tradeoff for new features and no maintenance, or to not have new features, and expect some cost added going in.
Because I’m old-school, a great used UK saddle, (in black, gasp!), would be good for me, as my needs are more simple, and the name does not matter to me. I think the Thorowgrood saddles are more every-day over there, something like Black Country or Fairfax saddles might command less of a premium on our shores, over, say a CWD, Antares, or such.
A Passier, or Stubben, or Butet would be great, I think, if you can find the least wear, and best price.
Isn’t that the whole trick tho?? !! Budget / Time/ Quality. kills me.