Eta 2846 is a good direct replacement and its stem height is exactly the same as a 2836-2. you can switch out a 2836 with a 2846. Direct swap... The dial, hands and datewheel transfer over.
ETA 2846
Features
automatic
sweep second
day: quickset, 2 languages
date: quickset
option: no day
Data
11.5''', Dm= 25.6mm, Do= 26.0mm
H= 5.2mm
F= 1.65mm
T= 2.25mm
17/21 jewels
f = 21600 A/h
power reserve 48h
Balance staff ETA 2846
Stem W3738
Mainspring / battery
1.23 x 10.5 x 0.11 x 450mm
Hands
1.50 x 0.90 x 0.25mm
Features
automatic
sweep second
day: quickset, 2 languages
date: quickset
option: no day
Data
11.5''', Dm= 25.6mm, Do= 26.0mm
H= 5.2mm
F= 1.65mm
T= 2.25mm
17/21 jewels
f = 21600 A/h
power reserve 48h
Balance staff ETA 2846
Stem W3738
Mainspring / battery
1.23 x 10.5 x 0.11 x 450mm
Hands
1.50 x 0.90 x 0.25mm