Quoted, "Email from SRS Microsystems: Yes there is a price increase in all Pentax lenses and it is across the whole range unfortunately. The prices will go up as soon as we order any new stock at the new prices. hope this helps."
Speaking of the UK lens price increase, it does affect the used market, see this bid, of which the asked price is just insane!
£1,347?! Pardon? Ten years ago, I could buy this lens at HK$3300 brand new (~US$423).
Ned Bunnell Has Made an Interim Response to the Recent Lens Prices Increase
Breaking Bad News! Crazy Price Increases of Pentax Lenses with Immediate Effect!
Sunday, April 15, 2012