emelex, heat molding the 23 will (should) alleviate any width, pressure issues. I don't know how well the heat molding does for length but that shell is very workable if you need a bit of room for toe length.
There is nothing worse than swimming in a boot. But, that said, an intuition has greatly improved some volume issues (too much volume in boot) for me in past. And that stock liner in the Backland is probably one of the top candidates for immediate replacement relative to what are a lot of boots with great stock liners these days. And an intuition is a more volumous liner (can take up more room, even the LV, relative to the stock one in this boot).
I can only assume you are ordering online, otherwise your bootfitter would be able to answer your questions.
I would go to a bootfiiter and buy the boot from them. They'll mold it. Tell them your price online and see if they'll work something out. It's not like there is any short supply of Backlands. Plus you'll have some recourse if it does not work out if they are a reputable boot fitter and care about their work.