driving RHD is not an issue for 95% of the people, it is a mind set, if you say "i can't do it" or "i don't want to" then you won't and that is fine by me. each to their own and the last thing anyone needs is someone on the highway driving a vehicle they are not comfortable doing so.
then there is the very few that can't drive RHD and really shouldn't be driving LHD either.
the cost will be what it is, once again we get down to the QUALITY of the conversion, you can do a fan belt conversion for a couple hundred or you can do a nice job for a few grand or if you want factory looking then it could easily go over $10K. power elec options are more of a pain than manual windows and door locks. finding a LHD AC parts can be a bugger. the signal lights and wipers will still be on the opposite side of normal. you need to convert the wipers over to LHD operation.
the swaping of the steering and pedals is the easy part although a brand new LHD steering box is about $2K by itself... suddenly a donor rig makes total sense.
so how clean a swap so you want? then budget for it. a wheeling rig can be a butcher job but a DD with wife and kids most people would want a astetically pleasing job.
the situation now is not can you drive RHD but the province you live in, if that province is exerting pressure to keep RHD off the roads then you have no choice but to do the conversion.