Recovering a HDD with Early Bitcoin

I mined bitcoin early in 2009 and found a few blocks, at the time it was worth nothing and was a novelty more or less. I believe this was before the first bitcoin pizza purchase. I left the wallet.dat on the hard drive without backing it up.

Now the exciting part! I still have the hard drive. I save all my old computers and they have all the original drives in them.

I always thought about that early wallet.dat file and that if the price of BTC went high enough I would recover it. I think I may have written over the windows partition on the drive so this is a bet that I can even recover the files. As a trial run I formatted a SD card and ran TestDisk on it to see if I could recover the files and how the software worked.

I have been really concerned I would mess the drive up or if I send the drive somewhere the bitcoin could be stolen without my knowledge or I could actually even be robbed. Early bitcoin blocks were 50 BTC each so theoretically if I can get the file it may have a significant amount accessible.

Currently I am leaning toward having a professional company go over the drive and be there in person for the process. The cost for the recovery isn't a huge deal since I have invested in Bitcoin for years and have the profits from that to pay for recovery.

Any advice on what you would do in this situation or finding a reputable data recovery in the US would be great!