This old XKs 090160 thermostat was available some years back but is not current: (above on wood with 3 cross bars on top and a cone) worked in my test in the XK120 application…the “top mounted” sleeve traveled down to block off the bypass. It does not have a small bleed hole. More on this version later. XKs now still has the 090160 on the web description, but also lists at the same time now, as part number , C3731/1. saying at the bottom of the view, that it supersedes the 090160.
I do not have means to test in a housing for 140/150 or early S1…but it “may” work as well. “May” because the 090160 sleeve is not as tall as the Smiths bellows type, thus covers less, and also it travels not from the bottom to up…but from the upper, downward to block the bypass. This may matter if it travels short or too far;!
Next case: the Barrett C3731/1, a single bar across the top, rounded center button on a brass top, a small bleed hole, a top mounted sleeve without bellows, spring is visible. SN%20Barrett%20therm%20sleeve%20type|500x500 
( SNG single top bar) a photo here also of the original type Smiths bellows/sleeve) Whether it in fact blocks the bypass completely on a 140/150, as it does on the 120 remains to be tested.
The SNG bypass thermostat…(and now the XKs as well) lists with the Jaguar part # C3731/1… but that means ONLY that they (SNG and XKs) selected that # designation for it, and determined or “feel” that it will do / fit what it is supposed to do where that # was specified by Jaguar. It is NOT a Jaguar part, nor are these thermostats the same as the Smiths type bellows/sleeve part that Jaguar used/installed at the factory. The SNG stat looks similar to the current XKs 090160…but some differences easily seen to the old Xks 3 bar version. Whether the sleeve moves “up”,.,or “down” is irrelevant IF: it is has enough sleeve material height to cover the bypass port; and if it moves enough, but not too far, to cover and close the bypass port. Seen here the SNG C3731/1, the XKs 090160, and a original type Smiths X85025. the old XKs has 3 bars, the current XKs C3731/1
090160 a single top bar & visible spring 
The older 3 bar, cone, silver top, brass closed bottom with no spring visible- 090160 is a 160C…on the cold side. It has no mfg name mark, it has “J04” “160 G” (prob mis-stamp in China and meant to be a C), and “13” all on the bottom smallish copper button base. This 3 cross tie bars on the top, with no bleed hole has a bottom that looks nothing like the single top bar 090160 ,this one having a closed bottom, no visible spring.
shown, a little blurred.but obvious differences,
Nick
XKs currently lists the C3731/1 090160, and the photo they show now is the single top bar, spring visible…perhaps the same as the SNG…so maybe the exact same thermostat. But XKs shows it as not available, whether a temporary issue is not yet known.