LB-501 is the most well known and trusted scale. I have one and it's worked great for a few years now. It's nice because it also comes with recalibration weights. However any good scale that weights up to 500g and in .01g increments will work just as good.
Honestly, the scale I purchased (it's the one recommended, in the readings for people new to DIY) doesn't work that good when mixing small amounts. It doesn't measure small enough - I'm talking sample 10ml sizes. All the flavors were poorly measured/weighed out & literally NEVER tastes how they were supposed to.
I literally use a small pocket scale, that is probably used more so for illegal activity. I've even used it to measure larger quantities - such as 120ml. I bought this one at a gas station.
I picked up this little guy when the LB-501 was sold out everywhere. I've been pretty happy with it but as others have said the LB-501 is the most popular so if you find it, I'd get that probably (looks like Amazon has some right now).
Since LB-501 isnt really easy to find, i went with SC-501-A scale from Amazon. Sadly its unavailable now, but they have SC-501 available for 40$ im not sure the difference but it may be that SC-501 doesn't have the AC cord that keeps it from auto-shutoff. Not entirely sure though
The lb501 is great, if you can find it. https://www.ebay.com/itm/500g-x-0-01g-High-Precision-Digital-Scale-SF-400D2-Counting-wit-USB-Wall-Adapter/381198858937?_trkparms=aid%3D555023%26algo%3DHOMESPLICE.SIMRVI%26ao%3D1%26asc%3D20191002091506%26meid%3Db091dcac15cc44089bc0079808a1a1c7%26pid%3D101096%26rk%3D1%26rkt%3D6%26mehot%3Dag%26sd%3D293731482421%26itm%3D381198858937%26pmt%3D1%26noa%3D0%26pg%3D2332490%26algv%3DSimplAMLv5hPointwiseWebNoToraCoCoViewsNoHighIdfOrRoundRobinBlenderWithPromotedViewItems%26brand%3DHorizon&_trksid=p2332490.c101096.m3021
This is good as well.