Couple of things to consider when picking encoders as a team in China.
It is usually much easier to get VEXpro parts vs AndyMark, VEX have a dedicated website for Chinese sales and the shipping is very cheap and fast from Shenzhen. The product pricing is also only slightly higher than the exchange rate and you do not need to pay expensive international shipping or taxes.
https://vex.hexbugvex.cn or https://www.innovationfirst.cn/ if you haven’t been buying from here already.
AndyMark use distributors in China who significantly markup the items, so it is better to just use VEXpro.
If you want to put an encoder on something which uses a VersaPlanetary Gearbox then use the Integrated Encoder, this works well and is a good encoder, the cables are just a little fragile so be mindful.
For the Data Cable to connect between the Magnetic Encoder and the Talon SRX, you can just buy cable and connectors on TaoBao and make your own which will allow you to reduce cost while being able to choose the length.
If you want an easy way to put encoders on your drivetrain consider using one of the NEO brushless motors with the integrated encoder, I believe REV is able to send these from within China meaning you won’t need to order from the US.
Otherwise there are plenty of decent reliable encoders available on TaoBao, you will be able to attach one of these directly to your axle and then connect it directly to the RoboRio.
If you send me a Private Message, I am happy to send you some links to specific parts or give other Encoder advice via WeChat.