Someone was building a 120 a while back but it presumably never got completed.
The 115s ran as 4-car non-gangwayed sets (DMBS, TS, TCL, DMBS) and were built for Marylebone-Aylesbury/High Wycombe/Banbury services, although 6 sets were initially used on Liverpool-Manchester services over the Cheshire Lines route. The class 115 DMBS had a smaller luggage section than the other related Derby-designed suburban units.
Class 127 (for St. Pancras-Bedford services) were similar to 115s but had a different formation (TSL in place of TCL), no front handrails and were powered by Rolls-Royce instead of Albion engines, so had a different arrangement of underfloor equipment.
Class 118 was the Birmingham RCW version of the Pressed Steel 117, with a more curved top to the 4-character indicator box (a few early-build 117s also had this feature) and most having front lamps from new.
There are quite a few first-gen DMUs available, but some are types that were withdrawn in the 1970s or are specific to a particular region:
Currently on UKTS there are models of classes 100, 103, 104, 105, 117 and 129, 121 (in post-privatisation condition), Derby Lightweight and AC Railbus;
There is Tim Court's updated Trans-Pennine 124 from BATS freeware;
Classes 101 and 108 from 3DTS (both in Cambrian 2?)
Classses 101 and 107 are shown in latest MT screenshots of SCE
