First Bike Build

Hey all,
I decided to build a MB and had been lurking on here the last few weeks for tips which way to go. When I saw the way the rear sprocket that comes in the motor kits clamped onto the spokes, I became concerned with it's durability and was about to give up on the idea of building a MB until I saw the $60 Manic Mechanic hub adapter and sprocket.
I noticed on the Manic web site there was a Schwinn Jaguar with the hub adapter. So this past Monday, I ordered a new RAW 66cc kit for $190 and started looking on Craigslist for a used Schwinn Jaguar or Landmark. Today I found a Jaguar for $80, everything was good on it. I got it home and went to measure the rear hub so I could order the MM hub adapter, only to see the bike had a concave shaped Quando hub. Dang it! Schwinn must have changed hub vendors on some of the Jags!
So my question is, what reasonable priced hub will swap out with the Quando so I don't have to by new spokes? Spoke hole circle is about 1.75", spoke flanges are about 2.125" wide and overall width is about 5.25".
Do I have any other options besides a new hub? I thought about a SBP shift kit but I'm already into this project for $270 and don't want to throw another $240 at it.

My hub has the shape of the one on the top right of this page.
I need one for a 7 spd cassette shaped like of one of the ones on the left. I hope to find one that will lace up without having to buy new spokes.

I posted a reply a few hours ago, don't know why it didn't show.
The bike has a 7 gear cassette. Apparently Schwinn used two different hubs on the Jaguars, Quando and Modus. The Quando, which I have, has a concave shape that I can't use. I think the Modus has straight sides which I need.
Mine looks like the one on the top right of this page. I need one like on the left side.

There's a girls Schwinn Jaguar 7spd that's for sale. If it had a Modus hub, I'd buy it, rob the wheel off it and keep the rest for parts. The seller has several MB ads on Craigslist so I think he puts them together. So I call, here's how it goes;
Q: What kind of hub is on the girls Jaguar you have for sale?
A: It's a 7 speed.
Q: Yes, I see in your ad it's a 7spd, what kind of hub is it?
A: The rims are aluminum.
Q: But what kind of hub is it?
A: It had 7speeds.
Q: Yes, 7 speeds, but what kind of hub?
A: I don't know what you mean by hub.
Q: The thing the spokes attach to and the axle goes thru, is there a brand name on it?
A: It's the standard original hub.
Q: Can you look at the hub and tell me what name is stamped on it?
A: If you want to know, come and buy it.
I wonder if this dude builds the MBs he sells any better than he answers questions.