[Hallicrafters] Why is the R-42 speaker so expensive?

[jeremy-ca]

Ive been watching the Ebay prices go over $300 for very nice ones and even 
around $200 for ones all scratched and missing the logo.

Why?  They dont appear to be that scarce and by todays standards the cabinet 
acoustics are marginal at best from what Ive seen in the pictures.

Are any other Halli speakers of the bass reflex design? Or am I going to 
have to pay and weep and make my SX-62A happy with a R-42?

Carl
KM1H