The most detailed and freely available maps of the Himalayas are those published by the Survey of India (SOI). Initially created as part of the The Great Trigonometrical Survey in the 18th century (en.wikipedia.org/wiki/Great_Trigonometrical_Survey), the maps map the mountains in stunning detail and were recently made freely available to the public through the SOI web site as the Open Map Series (OSM).

Maps are made available as sheets of 1:50K scale (1cm on map = 500m on ground) of 28x28km in size. Each map sheet has a unique number. Let's download the map sheet covering the Pangi valley around Saichu village. Below web site allows us to easily identify the sheet nr: 52d/9

https://www.indigeo.com/iMap.html#7/33.138/78.005
(Choose "Survey of India(SoI) - 50K Topo Map Index" in the layers / right toolbar)

Next, go to the SOI web site to download the sheet in PDF format:

https://onlinemaps.surveyofindia.gov.in/FreeMapSpecification.aspx
(login + enter 52d/9 + click download)

Note - not all map sheets are available on the Survey portal. Scanned copies of all (older) Survey maps can be downloaded from:
https://zenodo.org/record/3595575