Looking for a back-to-basics performance machine? Caterham has a whole range of models worth looking at, all based on the classic Lotus Seven. But if you’re in Europe, it may take a while to have your order fulfilled.

AutoRAI reports that Caterham’s entire European allocation is sold out at least until the third quarter of 2019. Part of the reason comes down to the vehicles’ popularity and the relatively limited production capacity at the small manufacturer. But another big factor comes down to regulation.

With the new Worldwide Light Test Procedure coming into effect, only some of Caterham’s models can be sold on the continent. It’s working to bring the others up to spec, but in the meantime, it’s only selling the 275 and 485 variants – with the 165 and 355 pulled from the market pending WLTP compliance, and the 620 series restricted to track use.

According to Motor1, Caterham sold 667 units around the world last year. And strong demand has it on track to match, if not exceed that figure. Those numbers represent a high-water mark for the niche automaker, which hadn’t sold that many vehicles since 1996 – long before AirAsia chairman Tony Fernandes took control of the company in 2011.

Caterham offers several versions of the classic Seven in the United States, including the 270, 310, 360, 420, and 620 series. The base 270 model packs a 1.6-liter Ford Sigma engine, channeling 135 horsepower for a 5.0-second 0-60 time and a 120-mph top speed. At the other end of the spectrum, the 620R is powered by a 2.0-liter supercharged Ford Duratech to run to 60 in 2.8 seconds and top out at 155. Buyers can opt to build theirs on their own or have them shipped as rolling chassis with the powertrain to be slotted in at the destination.