you can creat your own sight tube with a simple roll of paper or card. I have dont this and ti works perfectly to see if the secondary is aligned properly under the focuser.
if you plan on getting another scope, moving from 200mm to 70mm is quite a backward step. if its only for doubles you will see less stars and the dimmer doubles may be beyond the scope...
if you save your money, aoe have a 102mm f/9 on an eq5 ofr about $750 (+postage). i am considering this scope myself just for a grab and go scope