If you're after an affordable tilt/swivel hot-shoe flashgun, then Clifton Cameras have a clearance sale ongoing for the Sigma EF-530 DG Super (SO-ADI)
. See here
. £84.00 delivered with a 2 year warranty.
If you're not bothered about the warranty so much, Onestop-Digital have the same gun @ £99.99, but if you request a price match against Clifton, they'll offer it for £79.99 delivered. So it's £4.01 cheaper, but I'd take the warranty as the repair costs can be more than the purchase price if it's electrical. See the Sigma (UK) repair tariff on their website which are nett of postage BTW.
I have no idea if these flashguns are SLT compatible (I don't use the system), but as a bread and butter flash, it's a bit of a bargain compared to most retailers who still stock it. Anyway, don't shoot the messenger