Jota996, there is nil stock or likely to be any at RS. Checked the basic physical dimensions of the Omron EE-SX1088-W1, also listed as obsolete though stock on hand at Farnell is 354 worldwide, buy up big while you can i suggest to all. The Omron should drop straight in mount holes at 19m/m, slot width at 3m/m, height at 10m/m, fly lead out colours may need attention to data sheets. Electrical ought to be compatible, check that after my morning tea break.
The Omron exceeds the Honeywell electrical specification in all regards, both are only 85C rated devices, as such will suffer in the elevated cavity ambient in service, dependent on DMC static IR led current, the Omron has a more robust IR led as specified. HTH.
** checked all the common supply houses on the planet, Farnell is your last hope, if stock on hand is correct, buy big Lads, the clock is "ticking....love the Hives btw, new stage clothes the biz... "Hate to say i told you so..." about slotted opto's..
*** seems Element14 in Australia is holding the last stock, may be ordered through Farnell, though not sure of the inter company links these days, since Element14 is an Avnet division now, no matter online ordering is your friend. That wraps this up for me, this topic. Have fun. j