I have one of the pedal totes with the Gator GBus-8 which fits nicely underneath, but it does look a fair bit smaller than your PSU. I would say that probably wouldn't fit. On Thomann you can get the Gator GPT with the GBus-8 for around £70 which is a reasonable deal, mine has taken a fair bit of lugging between jams etc very well.
Thats what I thought. Ah well.... I've went and purchased it anyway. Its pretty much exactly the size I need. I may get a different power supply down the line, but I've already went a bit mental with pedals this month so I think it'l have to wait. This board from thomann seems to be super cheap though! I'm annoyed at myself because I only just bought a load of stuff a few weeks ago from them, and I've had to pay a 2nd delivery charge... but hey ho... its still cheaper than what I'd pay elsewhere