Replacing compressor unit question?

After 35 years of faithful service, my Sears compressor has died. I
was blowing the water out of the motorhome plumbing, getting ready for
the freeze. It took about ten minutes of blowing air into the intake
while my wife bled all the water out of the various fixtures. The
compressor was running constantly and, just as we were finished, it
began clanking like a '49 Chevy beating the babbit out of a rod.

Well, I've been meaning to drag it out from under the bench - no small
job, gotta move a lot of stuff, car, motorcycle, etc. to check the
specs on it for replacement. One that old, there's no sense
rebuilding. Before I could get a roundtoit, we stopped into HFT today.
They have a "3-HP" twin compressor pump on sale for $89. Can't beat
that! Looks just like the one on my compressor. I don't remember the
hp of the 240 volt motor I replaced a few years ago, but it's about
that.

They swearch all over the store for one NIB. Nada. They won't sell the
display unit that's bolted to the counter. They will, however, give me
the "5-HP" unit for the "3-HP" price. Wow! That's a $139 pump. I
haven't seen it yet because they have none on display, but I take the
deal.

I get home and remove it from the car trunk where the gut put it. Oh
oh. It's a V-twin instead of an inline. Examination of my existing
compressor motor reveals my first guess was right on. It's a 240 V. 3-
hp 2350 rpm motor. The other pump would have been perfect. Now what do
I do?

Options -
A - just take this one back and trade it for the smaller unit when
they come in.
B - Install this one (not as easy by a bunch) and try it. If it
doesn't work, buy a 5 hp motor.
C - Sell this one on Craig's list, maybe make ten bucks or not, and
buy the smaller unit.

I like "A". If it's "B", will my 3 hp motor run this pump? A 5-hp
motor from HFT is $300.

I don't need any more air than the old compressor supplied.

Rich S.