Basically copy coupon, view price history or create e-mail price alert. Best price?
Rated voltage DC 6-14.4 V, Maximum load power 198W, Stall (Stall) Current ~ 50A, 800 RPM / min, Model RS-550, Rated Torque 2kg.cm, No-load starting current 5 consecutive mean about 7.2A, No-load speed 22, Max. Torque 5kg.cm, Load current 3.65 A, Stall power ~ 550w
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. There are no coupons available at this moment in Banggood.
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG1714, elec, TS15prime, BGRU8542, BGCITYADS2019, AFfbG10, BG2020NS, BGVDay10%off, bGhOnEy10, BGherra, BgcLuBofErtA10, BG00c906, BGGines
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for DC 6-14.4V RS-550 Motor is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).