Get a five dollar wrench and tune it. Play it and see if you like it.
Sekova was the maker of Chromaharps for quite awhile. They can sound pretty good or be a total dud. As I recall they had slightly different sizes in the bars and felts from what Oscar's had.

Check EBay for values. I'd guess at $100.00 tops but you gotta add lots of value on top of the because it came from Grandma's house. And that value is hard to price out.

Don