I have a 29 string which is almost too big for a lap harp, and a bit too small for a floor harp. It has no sharping levers, and I usually keep it tuned (??) to C major.
I built it from a Hughes Dulcimer kit. (That's the company name) They are in Denver, Colorado, US. I did do some adapting to the kit. It's been several years, but I think the kit cost me about $250.00 US, and my up grades added about $100.00.
If you have any woodworking skills at all you can do this.I can probably scare up a website for Hughes if you're interested.
It's not the best harp in the world, but I don't play it very well either, and it's the only thing I could afford.