Hello Pax,
Yes you are right. Ever since RevellGermany released their 1:72 scale u-boat, the
market has been flooded with amazing aftermarket upgrades for this boat.
Unfortunetly, that is not the case with the smaller 1:125 scale U47 and U99.
Nautilus Models was selling a VII-B resin upgrade with a PE fret. The resin is
no longer available but you can still order the PE fret.
It is rather unfortunate that very little attention has been paid to these smaller
versions and yes they could use some retooling and upgrades as not everyone
wants to build the 1:72 version even though it being an awesome model.
So, try a little scratchbuilding. It requires a little bit of patience but it is not that
hard to do. And in the end, you will have some unique models in your collection.
You may even raise a few AAAHHH's at your local model shows!
Have a nice day and happy modelling,
Joe