The beds at Four Seasons Place are OK. Not super wide, but long enough. And should be just about within your budget.
Regarding Ikea: Ikea only sells these small beds in Asia, they burnt themselves the first time they tried to enter the Japanese market with selling the same size and style as they do at home in Sweden. It didn't work out that well and they had to pull out until they re-entered a few months ago when they opened their a store in Tokyo.
The most bizarre thing in Hong Kong is not the small beds, it is the small bedrooms, at some of the brand new apartments I had a look at initially, the bedrooms (!) were too small for me to stretch out my toes in, and I am only 183 (6ft) tall!!! That is ridicolous if anything!!!