SBI makes an improved charging handle. There pistol grip has a similar angle to original AR180s, and of course they have their Lynx upper and lower that will happily house your WKs guts (though their new Comp lower uses AR-15 standard safety cylinders and trigger pins). There are non-forum vendors like Third Echelon that have other WK parts, like a mid-length piston and matching mid-length gas port barrel.
