Re: What Guitar and Bridge is this?
The SA160 has been produced in various guises since 2000. Yours looks like the QM model, with the veneer top. The W denotes the factory (World Instruments) and Y is November; the next digit indicates the year, and the remainder a consecutive production number.
Bridge was a SAT30 in the noughties, I believe; stock nut is plastic.
If you wish to fit a Wilkinson/Gotoh type bridge (Wilkinson is made by Gotoh, fwiw), check the post spacing (centre to centre) and block length, if you have a match, then you can seamlessly retrofit a new bridge (Ibanez OEM and Gotoh are both metric). The Gotoh website typically lists all these specs for their bridges. They offer a number of two post bridges in different finishes in brass or steel saddle configuration.
Likewise, Gotoh tuners ought to be a direct fit.