Ugly ass amp
I've seen amps made out of old suitcases (cool), gasoline containers (not cool), beer cans, and backpacks, but this is the ugliest of them all. It's made from a PVC sewer pipe T. That's just the image that you want for your harp playing.
Actually, he shape of the six inch "T" is pretty good. There may be a certain odd aesthetic to the amp. I guess the guts would be the telling point on the quality.
You can buy a good IC stereo amp circuit board for about $20 and the T costs around $5. A 6 inch speaker goes for $10 at the electronics hobby sites. Throw in $5 worth of hardware and the thing can't cost much more than $40 before labor. $149 may be too steep, I'm guessing $79.99 is the right price for this. 

 

Buy the Book!

I cleaned up my tab for Sonny Boy's Help Me and made it into a short book. There's a Kindle version for 99 cents, and if you buy the paperback you get the Kindle free.

Playing "Help-Me" In the Style of Sonny Boy Williamson II: A step by step, note for note analysis of some of Sonny Boy's Signature Riffs