Hi Jay,
Nathan does use the La Bella 0760M 'Jamerson' set... as I do and Jet did when I worked for him... they are fantastic strings and feel and sound great... I can highly recommend the Jamerson set and the slightly lighter gauge La Bella 0760FM which are 49-109. If you want to replicate what Jet used, then go with the Jamerson set... if you want to replicate what Jet does with the Jamerson set, then use the lighter 0760FM as the lighter gauge allows you to dig in as Jet does... unless of course you are like Jet and have a heavy technique and hammer every note with 110% effort!
Having always been happy with the LaBella strings I was finding it difficult to justify the extra cost of trying the Thomastik strings, a decision not made any easier by the number bass players who rate them both very highly! Though I suppose I will have to take the plunge sometime.
I will keep you posted on the Framus front... though if it is anything like the Antoria it is a VERY slow process.
All the best.
Mark.