You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
Efficiency η: 85%, Rated load succession rate: 35%, Rated output capacity: 10KV.A, , Outline dimension (mm): 490*220*375, Net weight (kg): 17, Rated input current (A): 46A, Rated input voltage: 220V±10%, Output no-load voltage (V): 69V, Specification of welding machine: NBC-250, Power factor COSφ: 0.73
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 and price update (UTC):
Banggood
Banggood warehouse is located in Europe 
. There’s only 1 record in my database, so I have no idea if the price is OK. One coupon is available. Cool!
Link: Banggood product page
1. ($272.15): BGGines
apply code in your basket (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): BG6d2f05, BGTools8
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Not enough data to show price history chart… $299.99 is the only recorded price. It was not cheaper than that since we have saved it in DB.
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)).