A may give tubulars a try. I'm not so stressed about the flat issue as SF is only 7x7 and I don't plan on going on longer rides with this one. Worse comes to worse, on the bus bike rack it goes.
One last question though. If I go with vintage NOS rims, do they have breaking surfaces or do I need to get them machined. I was looking at a pair of old Nisi rims. I'll be putting a front brake on this.
Thanks for all your replies.