How is "Oelek" pronounced?
Sambal Oelek is not tied to any producer or manufacturer. 
Oelek is a word indicating something was processed in a pestle and mortar, and refers to the mortar (if memory serves). 

"Oelek" is the Dutch spelling for "Ulek", and the "u" is pronounced as the "u" in "bull", corresponding to the diphthong "oe" in Dutch.