Various deals on SodaKING including:
Refill Swap $14.70 (Reg $21)
Spare Cylinder $28.00 (Reg $40)
Syrups $4.20 (reg $6)
Also machines and spare bottles.
These are all compatible with SodaStream.
I'm sorry, I cannot see an expiry date for the deal anywhere, not for want of looking. I got a refill and a spare bottle in store today but there were no tags on the shelves that might indicate the duration of the deal (unfortunately many stores in my city are extremely slack about shelf tags, so this is par for the course here)
They seem to be having a "1 week only GIANT SALE". A google search for their catalogue suggest they run catalogues from Wed to Wed and this 1 week sale catalogue probably started on Wed Feb 8th. Meaning it likely runs til the end of tomorrow (Feb 14) or Wed (Feb 15).