My belt sander setup utilizes the combination of the 120V Swiss-made (by Scintilla) Bosch 1274DVS:
...the German-made Bosch 2608005026 sanding frame (with brushes and smooth plastic insert):
...the German-made Bosch 1608030024 bench stand (a.k.a. "subframe"):
... the Bosch 2607001079 sanding fence:
Sadly, the right angle hose adapter that was once available for this machine (Bosch 2600499045) was discontinued, apparently owing to its tendency to tear and fail within the first couple of uses.
There is a 3-D printed right-angle part that might work, though I haven't held one in my hand so can't confirm its compatibility:
www.thingiverse.com/thing:2493449
The accessories available for the Scintilla-made 230V and 240V versions of my same machine (known mainly under two main model codes: Bosch GBS 75 A or AE and the Bosch PBS 75 A or AE) - which share the same model/part numbers as those listed above - are exact matches for the accessories that were available for my machine. Be careful, however. The homeowner-level Bosch belt sander that is currently being produced, which happens to share the PBS 75 AE model identification and a similar green body color, is NOT a Scintilla tool - it's of a completely different design and is an inferior Chinese-produced tool. Stick with the above accessory part numbers and you'll find the accessories that are compatible with the various Scintilla produced sanders. This is true even if "1274DVS" doesn't appear as a compatible model on the box. Also, most spare parts (including armatures if you're a savvy researcher) are still available for the 1274DVS. Used and occasionally NOS 1274DVS machines occasionally appear on that well known online auction site as do the accessories. Plus, the accessories are available on Amazon UK and from other E. U. retailers.
The following video (featuring the OLDER Scintilla-made version of the 240V PBS 75 AE) indirectly showcases the capabilities of the Scintilla-made 110V 1274DVS. [Remember, aside from voltage differences, these two machines, like the GBS 75 AE, are - because they share the same body and mechanical parts - and for the purposes of accessories like the sanding frame, etc., identical.] :