Ahhh, now there's the £50 million question...
About 12 months ago it would have been easy. "737". Now? lots of folks running around with bare ratings. Maybe the A320? who knows at this stage.
ATR's? I know there are some operators that will train "outside" folk but whether or not they are familiar with what is required for a lic conversion is another thing. Likewise with Dash 8.
There aren't too many Shed operators around now.
The pay for rating job is getting more common here unfortunately. Therefore you do run the risk of "paying twice". Eg easyJet won't consider a type rating aquired from another TRTO unless you have +300 hours on that type. (Known as a TRSS). You might think, "bewdy, I'll get a job and I'll just pay for the CAA". Nope, they won't look at you. This applies to other operators too.
To get a feel for the market check out
PPJN