Yup. Condition and brand plays a more significant role in the price. When I first started hunting for 7734s earlier this year. I was snapping off any 7734 that was below a certain price, not paying attention to the totalisers. I ended up with 03 x 30 min watch and 01 x 45min watch. I didn't notice the difference until about 1 month ago, about 1 or 2 weeks before DW officially released the case sets.
But what I have noticed that since the news of the release, none of the 45 min totalisers went for less than USD250. I doubt that the price will go down any lower than USD300. As with any used watch (esp those from the 70s), it's always good to have a full service upon arrival, bearing in mind that this this will not be a cheap project.The case set itself will cost around USD500.00. The cost of servicing the movt + additional parts will give you peace of mind for the next 2 to 3 years.
I suppose that it all depends on how you approach this build.