I've got several Lectron Carb options between 34 and 38mm, but will probably go with 36mm powerjet type Paul.
As for pipe Swarbricks have been a favourite of mine, and he is now listing an improved power set in kit form which is ideal as I can tack them in place then TIG them off the bike.
Dennis Trollope has supplied a set of NOS reedvalves (kerching!) and TZMike produces inlet rubbers which are winging their way over as I type.
There are still lots of niggling little issues to decide and sort out one of them being the ignition. I have sort of convinced myself to get a Zeel and go total loss with a lithium battery, as they are a reasonable price.
The annoying part is waiting for all of the small parts coming in from various suppliers as each part is holding up a stage of the gearbox assembly.
One other part giving me grief is the throttle. Standard TZ750 twist grip has four cables and you need a second mortgage if you can find one, being magnesium. So I'm looking at using a V Twin TZ twin cable twist grip with two splitters in each cable. I've tried buying various cheap twin pull cables off ebay to look at but they mostly don't have enough pull range for the larger carbs.
So the next thing is to contact Venhill to see if they can offer any suggestions.