The lugs are 18mm if you wish to change. This fine example is from the 50s and is sold as watch only (no box or papers). It features plastic crystal and two crowns. And one for setting and winding (applying power) the Alarm feature.
eBay
For Jaeger LeCoultre Watch Silicone cowhide Strap Silver Rose Gold Steel Folding Clasp 16mm 18 20mm Deployment Butterfly Buckle
Aliexpress UK
In what I would describe as amazing condition for its age - the watch doesn't look to have seen much wear over the years.
eBay
18mm Stainless Steel Deployment Butterfly Buckle for Jaeger LeCoultre Watch Silicone Strap Silver Rose Gold Steel Folding Clasps
Aliexpress UK
Also has a large Jumbo 37mm case excluding signed crowns and a Lug size of 18mm and a case thickness of 13mm.
eBay
16mm 18mm 20mm Stainless Steel Deployment Butterfly Buckle for JAEGER-LECOULTRE Watch Silicone cowhide Strap metal Folding Clasp
Aliexpress UK
Case size 37mm | Lug to lug width 45mm | Thickness 12.5mm | Lug width 18mm. The more watches we have the chance to see and work with, the better! This excludes the price of a polish. Watch Sales Ltd.
eBay
Quick Release Natural Rubber Watch Strap for Omega SEIKO Breitling IWC Oris Jaeger LeCoultre 19mm 20mm 21mm 22mm FKM Watchband
Aliexpress UK
The watch sits on a new Hirsch alligator skin strap with gold plated Hirsch buckle. In the early 1900’s Jacques David Le Coultre joined forces with Edmond Jaeger to create Jaeger le Coultre. The inside case is signed ‘Acier Inoxyable’ and ‘Le Coultre Co’.
eBay
Stainless Steel Watch Buckle For Jaeger-LeCoultre Watch Band pin buckle Clasp 16/18mm Bracelet Accessories
Aliexpress UK
Period: Circa 1960s. The cream dial retains its original character with minor marks consistent with its age. Watch Specifications. Serial Number: 713814.
eBay
Maikes Top Quality Leather Watch Strap 20mm 22mm Accessories Watchbands Braceletes For Longines Jaeger-LeCoultre Watch Band
Aliexpress UK
Overall, this is a well-maintained example that has been thoughtfully cared for. •Material: 14K yellow gold. ✔ Watch only. •Hardware: Yellow gold.
eBay
18mm Deployment Butterfly Buckle for Jaeger LeCoultre Watch for Silicone Cowhide Strap Steel Folding Clasp Bracelet Accessories
Aliexpress UK
We will look for and suggest the best products on your behalf. In good condition, the dial has scuffs and stains.
eBay
Real Cow cowhide Watchband For Jaeger-LeCoultre Master Series Curved cowhide Watch Strap Soft and Waterproof 19 20 21MM
Aliexpress UK