Just check coupons out (with price alert and history). You probably want to know what is the best price?
Item Name: 1506 3000KV 4300KV 4-6S Brushless Motor, Configuration: 9N12P, Motor Dimension(Dia*Len): 21.3×27.6mm, 3-4S@4300KV, Internal Resistance: 110mΩ@3000KV; 55mΩ@4300KV, Max. Con. Power: 450W@3000KV ;400W@4300KV, No. of Cells (Lipo): 5-6S@3000KV;, Version: CW Screw Thread, Model: GTS-V2, Color: Titanium / Pink (Optional), Max. Current(30s): 20A@3000KV;25A@4300KV, Idle Current(10V): 1A@3000KV; 1.6A@4300KV, Stator Diameter: 15mm, Shaft Diameter: 3mm, Stator Length: 6mm, Quantity: One PC, KV: 3000KV/ 4300KV (Optional)
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.
Link: Banggood product page
1. ($23.37): BGGAL8
2. ($23.37): BGRCParts8
coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGV21506, AFfbG10, BG12MRP, BGVDay10%off, BGMPB2020, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10, BGDAVIS, BGHONEY2110, Parts8
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Here is price history (for all/most countries) for RCINPower GTS-V2 1506 4-6S RC Motor.
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)).