Approach potential flight schools with the following idea;
Combine the necessary training with your instructor ratings.
There is no LH seat requirement for any of the check rides.
So train as required for the FAA IR from the RH seat to prepare for your CFII (Certified Flight instructor Instrument).
Same with your CPL SE and your CPL ME.
So you take three checkrides from the RH seat, IR, CPL SE and CPL ME.
The following week you take your three instructor rides.
This way you need to fly teh houyrs only once instead of twice.
Any CFII course worth their salt is about 15 hrs of flying (10 lessons or so).
This will be about the same as what you would need for the IR.
You need 15 hrs PIC ME for your MEI so that should all be training which is the same as CPL ME except a different seat.