Not a mandocello per se, but I do play tenor guitar, which is traditionally tuned CGDA the same as a mandocello. If it is something that interests you, but you don't want to sink a lot of bank into it, I can recommend the Kala tenor guitar from there site
https://kalabrand.com/products/ka-gtr Kala is a well known ukulele brand, and they came out with this a few years back. It's a bit shorter than a traditional tenor guitar that is 23 inches vsl but should not be an issue.