If that's the original rim I'd think about getting it changed too, the stock modern twin-wall ones aren't silly expensive, and there are some much nicer rims out there, the Sun Ringle CR18's are well made, the Velocity Aeroheats are lovely and if you have the dollars there are some staggeringly beautiful rims made by Andoza (the Hawk B1's deep-section alloys in a variety of finishes) or the carbon fibre ones from Hylix (standard section), Joseph Kuosac or SMCBike (both deep section).... if you go for deep-section rims you will need valve extenders on your inner tubes, though I have seen tubeless Brompton rims.... possibly Ridea...?