External M2 enclosure for my iMac 2013?

I have an iMac 2013 which is Thunderbolt 1, and most external exclosures for M2 drives I found so far is USB-C connection. Is this compatible with my iMac’s Thunderbolt 1 with an adapter of some kind, or are there Thunderbolt 1 enclosures for M2 drives on the market?

PS. I am talking about PCIe M2 drives, not SATA.