I have a Robin Casaday TGAD that does this, if you can find one used.
ADM sells something similar called the DSBS-MAX and the DSBS-MiniMAX.
Waikoloa, HI 96738
From: ap-gto@... [mailto:ap-gto@...]
Sent: Thursday, February 12, 2015 7:23 AM
Subject: [ap-gto] Parallel Mounting on a AP1100
Just wondering about the feasibility of mounting two scopes in parallel on my AP1100. For example, 5" refractor and a small (9") CAT or another wide-field refractor. If it's feasible, suggestions as to hardware and methods for alignment so each scope is pointing at the same place. Thanks!