Transformers headroom and "mandatory" components
If you have a bridge rectifier and smoothing capacitor that feeds your load then it's likely that your prefered transformer is too feeble: -



This picture came from this pragmatic doument produced by Hammond.

What you have to remember is that the DC output is going to be 1.4142 x the RMS secondary voltage (minus a couple of diode forward drops) and with a 12 volt secondary, the DC voltage will be about 15.6 volts. If you are pulling off a current of 88 mA, that's a load VA of 1.37 and the transformer is only rated for 1.1 VA (12 volt x 0.09 amps).