Does anyone know if I can replace a movement on a Casio pro trek and where to find the part?

Serial numbers are always in the back of the case or on the movement. Take to a local jeweler.

Vintage Croton Watch: Identification and Value Guide

Valuable Antique Detector https://www.txantiquemall.com > vintage-croton-watch
Model/Serial Numbers. The easiest way to identify a fake is to check its serial numbers and run a quick search online to confirm if it's a genuine model or not.

‎How To Confirm Authenticity of... · ‎Value of Vintage Croton Watches

Anyone know how to tell when a Croton watch was made?

WATCH TALK FORUMS https://www.watchtalkforums.info > threads > anyone-...
Dec 8, 2011 - I would suggest getting the caseback opened and find out what movement is inside and enter the number into the search box of Roland Ranffts ...

Missing: Chronomaster ‎' Show results with: Chronomaster

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THe PRO-TREK watch compass is very sensitive to nearby Iron (eg. cars, fridges, steamships, artillary canons, battering rams, guillotines, etc) and anything wearable or embedded in your body. I had to calibrate mine in the middle of a baseball field.

Get in touch with Casio support: http://www.casio.com/support

Better is to replace at nearby casio service center. otherwise look out here:
http://www.tiktox.com/casio-straps-and-spares/pro-trek-straps.html
or
http://www.watchbands.com/category.aspx,,categoryID,,767

try this link > http://www.watch-band-center.com/watchstrap-s1237h243-CASIO-Straps-Metal.html

The problems is very simple: On the back cover (inside) is a little Cu metal Part. This part is glued to back cover using a poor glue (rubbered glue) and, in time, is moving from original position. You must put back this parts to original positin ( a little hole inside of back cover) and glue using a good glue. When the back cover is mounted , this part must have a ferm contact with two springs from mechanism (sensor for back cover open). If beatwin this springs isn't a electric short (using Cu metal parts) the internal mechanism of watch "see" the back cover is open and show "OPEN" on screen!

Click on my profile (escapement), then click on Tips and Tricks. There you will find link to all CASIO watch manuals. Rate me, please

You can find details here: http://world.casio.com/wat/download/en/manual/
Rate me, plz.

Sorry we do not have parts here or any means to locate them.

Send it into repairs and they will send you an estimate on what it would cost to fix it. Give them a call at 800-706-2534 option 2.