Link left cold - Its a few sets at a buy-it-now of $40.

Front and Back.  The Front looks identical to a 556 sight, the rear is that target 22 diopter sight that works but looks odd on a Sig.
I don't find these often, thought i'd pass on to the group.

https://www.ebay.com/itm/405050338428?itmmeta=01J0ZV84E6TCG8R38J5G8J6YRD&hash=item5e4ee1ac7c:g:ZNYAAOSwJttmdIv5&itmprp=enc%3AAQAJAAAA4GApmTyFr6ZLLV4Ta%2Br4akfxrF%2B0oCEXaVYkp2mCdvPcWVFVcpdzN3WSOX%2BWcxbhaPdwY2u44Om%2BFU8QJLpRzopc0QguTit2VXel4eXnA0ctURaF8CGjvxkttqd3vQEgCG6u5g9ztDFC0ZHAms2JLAEjo77gIgfyZvK8itvyv15tdkwQvpNwJcu2Ilg67%2BXNeRw3guiBiTzfh5D7KQhcA6NRrBInJx2%2BkNXpMtigKT6m7lOS%2FnxP5%2BdRNpcAPltIZcpxJPMao5zt5YpAy%2FYzdWktGo%2BDg86%2FVdylFsXvemrr%7Ctkp%3ABk9SR5THoPuHZA

Thanks...grabbed a set for my 522.

Dang, missed out.  I'll have to keep an eye on ebay now.  Been looking for a sight set and buttpad for almost a year.

AGP Arms says it has a Sig 522 buttpad.https://agparms.com/agp-arms-buttpad-for-sig-556-and-sig-522/


and for sights, (front anyway) I ordered some GHK airsoft clones sights from their distributor (Samoon) that has parts.  I will report back (whenever they get here) if they fit the 522 fron sight dovetail.  The GHK Sig airsoft copies cost more than a Sig 522.

Parts are reasonable - shipping is high - like $30+ for cheapest option.

I was looking at their parts considering making the 522 into a 552-ish clone but pausing to see what some of the parts look like

https://samoon.com.tw/p-553/553-04

a flip-down sight is best for a red dot.  The fixed hooded sight can be a bit "busy"

I think I agree, I got the set from eBay and fitted them on - and it is "very" visible through the red dot.  I am going to sight in the irons today and put the red dot back on.

When the flip sight gets here from Samoon - I will see how that looks.  Nonetheless given the rarity of a sight kit, glad to have it as part of the gun.

Thanks for the AGP reference.  I ordered and received a new buttpad and it fits perfect.  Finally I can shoulder this rifle.

Giving up on irons and just running a rds.