Why not just remove the handles, pop out the lock cylinders, and clean/lube. If there are any defective leaves in the tumbler you will see them and can remove them. If you remove 1 or 2 out of 12 to 14 leaves, the lock may be slightly less secure, but most importantly the same key will still work.

This is a pretty easy job, I did my driver's door lock a month ago when it seized. I did have to remove a couple leaves as they were bent either from not enough lube or from trying to force the lock to turn (by me). Now the lock works like new!

Cost was about $2.50 for graphite to lube after I soaked and cleaned all the parts with engine degreaser and a toothbrush.

Do a search - there's plenty of info here (including my resulting post).

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