these in my opinion are the best CRT lenses you can get

Barco HD117-24  is a short throw (1:1.1) super high resolving lens for all usable home cinema screen sizes.
max screen width for HD 117-12's is only 60 inches while for HD 117-24's the max is 268 inches
HD 117-12 has a 1.2 throw ratio
HD 117-24 has a 1.1 throw ratio
THESE ARE ESTIMATES the following is confirmed
HD117-12:     Screen width from 2.0 ft./0.6 m up to 5.0 ft./1.53 m
HD117-24:    Screen width from 5.0 ft./1.53 m up to 22.3 ft./6.8 m

the HD 117-24    are ultra rare lenses and have a near perfect throw distance for home cinema use unlike the similar HD 117-12

a bit of interesting history, I removed these from the SEPECAT Jaguar flight simulator at RAF Coltishall in about 2006 when the Jaguar SEPECAT was retired from service.

as photographed (serial numbers will differ )

they have been in heated dry storage for 18 years, but there is a small amount of hazing and fungus,
which can be cleaned by disassembly, but in my opinion its very minor and not significant enough to be necessary

these very expensive lenses ( when new ) can be used as intended or used for your own DIY optical projects
( dismantled and elements used to make telescopes or massive binoculars )

UK postage is £15

MORE LENSES of various types ( 5 - 12inch ) are AVAILABLE ( ASK )

various TUBES ( 100+ new and used  ) are available ( collection only )  ( ASK )

late model 1999-2003 working Barco 808LC retroblock projectors available to suit these lenses ( collection only )  ( ASK )
some have advanced geometry boards fitted.

all parts and complete projectors available ( not cheap but available if you need them ASK )