That's called a "bolo" machete (or "matchet" in WWII Australian military parlance). It's a Canadian contract version and probably worth between 50 and 70 quid to a collector. If the leather scabbard is in good nick then you're laughing. Note that the one in the ebay ad is actually brand new. What looks like corrosion and gunge is actually dried cosmoline and wax paper remnants - tropic-proofing. Both the Matchet and the scabbard would clean up to an almost mint condition. Because it is an early issue (1941-42ish) it has the leather scabbard instead of the canvas one. As you can imagine leather scabbards didn't last long in the humidity and rain encountered in military operations in the jungle, so it's come out of stores, never having been issued.
That pattern of machete was the most common Commonwealth issue during WWII. British and Aus versions can be distinguished only by the maker's marks and the fact they have chequered bakelite grip scales. The big fat area near the tip of the blade chops deep with less effort in the same sort of fashion as a kukhri, so it's an effective tool for jungle use or for clearing light scrub in a temperate zone - just takes a lazy swing of the arm from the elbow, combined with a light flick of the wrist.
If it were mine I'd keep it and use it, but look after it.