Yes -- there are db-25 type connectors with coax fittings for 75 ohm, so
you may need baluns to do this properly.

***
Had to read up on baluns, and have no clue where to get the db25s w/ coax
fittings.... I wouldn't have to build anything if I found a simple way to
get LOTS of coax rcas down to a single cable. So far I only see 10c rg59,
which I could put rca compression ends onto, OR the ready made hosa 8channel
rca snake, but that looks flimsy - and I'm not sure it's best for all kinds
of transmission. Don't all those different hifi connectors (below)
generally enjoy different impedences?
***


I wouldn't use RCA type
connectors for this purpose in any case. They're really not
sufficiently well shielded and you can't lock them in place.
You're going to have lots of different signals inside the box, right?
Shield. And be sure to ground one end of the shield.


***

I wasn't very clear, as Crowley pointed out, but I want to take various
connector from a Home Theater Receiver as one cable to the TV (component
video, s, composite, audio, digital, whatever) So, I have to use rca
connectors /i somewhere /i.

It sounds like $100 dollars for an 8 in, 8 out, 2 box snake is quite
unreasonable. My figures were $280 for a complete set 1 main box, 4
separate output boxes and 4 DB25M - DB25M cables when accounting for $20/hr
labor for soldering, wire prep, box hole drilling, applying decals.

Sobering reality.

Thanks.
-Jessop