Here's an August 1980 ACTION MAN advert (reprinted from BATTLE ACTION) promoting erstwhile Space Knight ROM's inclusion in the UK equivalent of the G.I. JOE toy line.
But... good luck spotting him. The purpose of the advert was - beyond flogging the toys - to promote a drawing competition to design a suitably bizarre alien creature (note: they have to be a "space enemy", no friendly monsters here!) for the suddenly space-bound Action Man (this was post-STAR WARS... and sales of the old soldier were falling fast) to have a close encounter with. So, it makes sense that Ron Smith's extra-terrestrial beastie should be centre stage. But Rom, despite being "our only hope", is barely visible (someone - probably belatedly - obviously spotted this and added his name to his back pack).
I imagine Action Man manufacturer Palitoy did a deal with Parker Brothers to import a warehouse full of unsold Rom toys and - rather than sell them as a standalone item - bundled him into the Action Man line to hastily bolster its SF credentials.
All this was happening whilst Marvel UK was merrily reprinting the US ROM strips (in FORCES IN COMBAT, FUTURE TENSE and - latterly - STAR WARS) with a completely different continuity. Copies of the original US books were also appearing in British newsagents, as part of the monthly consignment of imported US Marvels.