The movement is a 2824 CHS timebomb with fake 3285 engraving.
You can read about it in the two threads below. This movement has two major flaws - an ultra fragile jump click spring, and an intermediate datewheel (IDW) that pops up out of place randomly and disengages the hour wheel (and the hour hand).
GMT Movements Explained
Fix for the GMT timebomb movement
Your seller listed the part below as included, but without further explanation you can't know what it refers to. Perhaps you could ask him.
Genuine spring:45€
There is a vendor (Ben) in Belgium who sells stronger jump click springs. If your movement has one it could be scavenged to add to a new movement. These springs are not "genuine", but they are better than the fragile stock rep part. If you are going to all the trouble of a new movement, you may want to buy one of Ben's springs and have it installed if there isn't one in your old movement. There is a link to Ben in my second link above.
This is an equivalent movement you can get from Ali Express. Note that it has a plate on it whose purpose is to contain the IDW in place. You can see my solution for this issue in my second link above.
https://m.pt.aliexpress.com/item/100...5002465055687&
Note: Using Google Chrome I get to this movement on Ali Express but not when using another browser. So IDK if the listing is gone and my page is just being pulled up from cache. Search on AE for "3285 movement".
You can also try to source one of these movements from a TD. You would need to be very specific about which movement you want. It would cost about the same and take about as long. Delivery from China is slow right now and there's a National holiday there Oct 1-8.
If after talking to your seller you determine that the "genuine spring" is NOT the one from Ben in Belgium, it would be potentially beneficial to order one of them and ask your watchmaker to install it. It's possible that your jump click is broken and that's all it would take to fix your movement.
Good luck