OK, it's not quite the crowdsourcing exercise you think it is, so to make up for it, here's a poem:
I have a desk, made by ROC,
It has a drawer, with a lock,
I have no keys; leaves me displeased,
If I find barrel manufacturer, it'll make me happier.
Does anyone have such a desk and therefore any indication from the keys they have as to who makes the barrels for these things? There's nothing printed in the barrel itself.
Then, I can get some new keys cut for a few quid based on the 3-digit serial number on the barrel.