I have always had to comply with the new codes on remodels, unless I got a waiver or a hardship and those are next to impossible to get, so they aren't worth messing with.Here I have done several baths where clearances for toilet and showers have been smaller than new code and the only way to correct it would be take over some part of a bedroom or hallway, building dept has never require I move walls to accomodate new codes unless I reframe the entire room.
Offset flanges can help you in cases where you need to slide a toilet over an inch or two, also you can use 9 or 10 inch rough in toilets instead of a 12" rough in to get more clearance in front of the toilet, some solutions are not that tough if you know what is available to deal with it.Yeah I hear ya, I work alot on 1920's homes where nothing is up to code. Basements here have 6'8 ceilings, they allow it etc... I only do residential and have yet to be made to move a toilet 1 inch to the right for 15 right and left, glad I live here cant imagine adding 2-3k on every job to move toilets sinks showers a coupl of inches.
Call your local plumbing supply outlet to see what they might possibly have in stock. Or do what I did Google it "wall mount bathroom basins" found this for an example http://bluebath.com/images/uploads/WH118.jpgwhere can i find a 12"Length x 18wide sink? anyone have an idea?