[Amps] Henry 4K Ultra Amp Question

[zilassoc at la.twcbc.com]

Is there a replacement blower that will properly flange up to original 4K Ultra mounting hole pattern, fit inside the available space, provide 140 cfm or more, and be relatively quiet?  Am I asking too much?  My research yielded not a single mounting flange that fits. Only as a last resort will I want to put in an adapter plate. Anyone able to help me?
Thanks for any help and guidance.
73,
Pete - K5PZ
zilassoc at la.twcbc.com
k5pz at arrl.net