This would be trial and error I'm afraid. The age difference is just too great where these two products would be designed to work together. You didn't say if your old drive was internal or external. If external, you need to get a PCIe SCSI 320 LVD card for the Gen9. It would need to be an after market card I believe. If internal, you would need the same but might also need some power supply adapter cables.
LTO retains read compatibility with two prior generations with and write compatibility with one prior generation. A review of the ML150 QuickSpecs https://www.hpe.com/h20195/v2/GetPDF.aspx/c04447843.pdf indicates that LTO 4 and LTO 5 drives are standard available options on this server so you may be better off purchasing one of these. The LTO 5 drive could read your LTO 3 tapes (for restore purposes) or the LTO 4 drive could actually still write to them.
So, it really depends how inexpensive you want this to be and whether you want to move to a newer LTO standard at the same time.
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