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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):
Residual Noise <1mV ac, Weight: 2kg, Power Consumption: 36W, Signal-to-Noise Ratio: -80dB / 3W, Output: Banana Jacks, Input AC Voltage: 100-250V AC, Dimensions: 124mm (w)x 132mm (d)x 166mm (h), Output Impedance: 8/4 ohms (Japan Z11-EI48*24 Output Transformers), Input Impedance: 10K ohms, Input: RCA Jacks, Input Sensitivity: 500mV, Power Output: 3W+3W @ 4/8 ohms, Frequency Response: 30-40Khz (+-1db), Power Tube: 2x 6P1, Voltage Tube: 2x 6J1, AC: Standard IEC Jack with Fuse protection (2A Fuse)
Banggood
Banggood warehouse is located in China. I can’t find any active coupons for this product 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): BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BgoFErTaSchInA10, BGELIG0920, BgcLuBofErtA10, BG213841, BG213841N, BGCuponation10, 7bcdf9, BGHONEY2110
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for APPJ mini2013 6J1 6P1 Vacuum Tube Power Amplifier? There we go.
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)).