Weaver makes Bases for the 673. The 673 has a Model 7 action, so it shouldn't be very hard finding a base and ring set up for it. I chose to use Weaver.
You might have a problem if you have a scope bigger than 40mm, as in 3x9x40. I put a 3x9x32 on mine with no problems at all.
If you have a longer scope, you may have a problem with the scope touching the rear sight. In that case, Weaver makes Off-set rings.
When I got the rings and bases for my 673, I bought one offset ring and one regular ring, even though I had the smaller scope. I used the offset ring for the front mount, but I suppose you could buy two offset rings and use them both, should you have a scope that is a little longer.
Getting the scope set up on a 673 is a litle tricky. You need the scope back far enough so it doesnt hit the rear sight, but you need the scope forward enough so you get the proper eye relief, without being crumpled up to shoot it. Offset ring (or rings) help you do that. As for the vent rib, you will be somewhat restricted as to the size of your front lens for mounting on a 673. I am not a fan of mounting scopes high off the action to make them fit guns like the 673, which is why I picked the 3x9x32mm.