I have one sounds exactly like this one - same year and mine also made in GB!
It is a 3/4 size machine instead of being 1/2 size like a Featherweight. Still petite and very cute. VERY heavy though, even for its small size.
I got lucky with mine - I bought it at a thrift shop for $45, got the machine, the case, and the manual. It was "frozen" when I bought it, but just from old oil. Cleaned and lubed her up and she sews perfectly; didn't even have to adjust tension much. I didn't find a single speck of rust. I had to buy a set of feet separately, and my case is not in great shape but the machine itself looks practically new. My prettiest machine, for sure.
I kind of feel like $150 is a little high. I love mine but I wouldn't have paid that much. I'm not really sure what they sell for online, though - might want to look at completed listings on eBay and see what they're going for "out in the wild". If it comes with a ton of accessories that makes it more appealing, but they're also really easy to find separately because they're standard Singer low-shank pieces. (I bought a whole box of feet in a nice vintage green Singer box at an antique shop for $12, and a vintage Singer buttonholer and zig zagger for $5 each at a thrift shop.)
Mine also has very plain decals, if this one has snazzy decals that might make it more valuable.
Here's mine: (The case is more battered than it appears to be in this shot.)
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