Find the Totally Tubular thread on C&V.
Don't buy them glued. If you can't glue yourself there is just no point.
Flats are easier to change with tubulars. You must know how. You must carry a spare and an inflation device. Spare tubulars rely entirely on air pressure to hold them in place and you will need a pump that reliably puts out high pressure. Tubulars do not flat as they did forty years ago. About same as equivalent light clinchers.
Tubulars ride better than anything. That is why they still exist. There are cheap nasty tubulars that ride only very slightly better than equivalent cheap nasty clinchers. Buy the good ones. The good ones also flat less and are far far easier to mount and glue.
Availability is a problem. Almost exclusively online. Maybe swap meets. Current top tires are $50-$60 delivered from the English discounters. Say Vittoria. Say Veloflex.
There is no resale value on those wheels. They come with pads? So carbon rims and rim brakes. No market for that. Bargain the price down even further and spend the money on a few spares. Really bargain. For a Cervelo I could build alloy wheels only slightly heavier and much stronger, much more serviceable for maybe 600-800. Serviceable but not Cervelo bling wheels could be even less.Vintage wheels could easily be lighter but they won't work with 11speed.