I think I can address this one; if anyone has better insight, please speak up ...

With the Sure IRS2092-based module you need a full power supply not just a transformer. The amp module specs suggest 55 - 65 volts; (you'll need to be closer to 65V for full power). The power supply can be a switching mode power supply (SMPS) or a linear supply. If a linear supply, for say +/- 60 volts, you'll need a transformer capable of 60V/1.4 = 43V, that is, +43 volts and -43 volts with a common ground. Also I'd guess you should be looking for 8+ amps output capability. Thus model Antek PS-5N42 might be better.

The Sure Store seems to sell only SMPS; (they are self contained and don't need a transformer). If you want a linear supply you'll have to find one elsewhere.

Another Internet provider that I've heard of is Connexelectronic, HERE. They have a pretty good range of Class D and Class T amp modules as well as SMPS and linear power supplies, (but no transformers). So for the Sure module, Connexelectronics can provide their PS2-6C dual rail linear supply, HERE. You'd need at least their 63 volt, 10,000 uF version or better yet, the 71 volt, 18,000 uF ...