I'm sure they'd be fine with you posting them in the jobs thread:
https://forums.overclockers.co.uk/showthread.php?t=18483999
But if you're working for a recruitment agency then it might be a bit dodgy/count as business promotion rather than simply doing the community a favour. The jobs thread is usually people posting vacancies at companies they work for, you can go to any number of websites if you want to find job adverts posted by recruiters - what value would yours be adding?