Unfortunately, according to CAP 682, the minimum training required for a 'small turbojet' is 10-15 days theoretical knowledge, 16 hours procedures and systems and 10 hours flight training. Not to mention the aircraft hire and test fees for the Licensing Skill Test and ATPL Skill Test and the CAA's pound of flesh for the issue of the type rating.
I think the repeat IR course may turn out to be the cheaper option even, God forbid, at OAT's obscenely inflated prices.