I wouldn't dream of paying for a crossbreed puppy.Pounds and rescue centres are filled with them.I work hard for my money and have no intention of rewarding lazy and irresponsible breeders who breed purely for commercial gain.
Much better to spend your money on someone who actually cares enough about a breed(any breed) to breed pedigree dogs and do the relevant health tests in the best interest of the breed.
It shouldn't be hard to get a cavalier in the larger size range,in fact many are let go as pets for this very reason.
Many of these large dog/small dog crosses could be a minefield for musculoskeletal disorders,plus you'd lose the cavalier personality and temperament with the cross...and that would be such a very great shame.
Sharing my sofa with Holly, Ivy,Lilly and Hazy.. and never forgetting our beautiful Daisy who reached the bridge too soon.