The cut in the slide is the same for all of this series of pistols. So you could use the fixed rear sight from the 422/622/2206 which is still available from GPC.
IMO this is the best low profile sight for this pistol, since you can't get the white dot version.
Beyond that you could go for an adjustable sight. After market ones show up on GB and EBAY periodically. Be aware that the 2206TGT uses a different dovetail so the sight from it, will not work.
I haven't validated it, however I bought a NOS slide a few months ago. The seller indicated it was late in the run, S+W started using a Novak sight for replacement slides. I contacted Novak, they were very responsive and indicated the sight appeared to be S&W 3rd gen/1911 handgun rear sight. I have not verified this so YMMV.
Here are some pics of different setups.
Aftermarket adjustable sights.
Novak
S+W target adjustable, no dot fixed, NovaK