Go down and check coupons out. Remember to check price history if it is available. Let’s see what best price is ATM.
Transmission Distance 10m, Working Time (h) 8h, Charging Time (h) 3-4h, Microphone Yes, 3.7V, Diaphragm Size 90mm*2, Output Power 10W*2, Standby Time (h) 72h, Frequency Response 65-18kHz, Connectivity Bluetooth/ AUX-in, Battery Capacity 2000mAh, Bluetooth Version V4.2, Unit Size 58mm*2
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 China.
Link: Banggood product page
1. ($79.65): BGSS10%SW
2. ($81.50): Email5
you should apply the coupon in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Old coupons (from the oldest to the newest): 502C6B, 04cc31, BGCITYADS2019, AFfbG10, BGVDay10%off, EARSP11, BGAFF10OFF, bGhOnEy10
(there’s a little possibility that old coupon will work)
Price history and price alert
Here is price history (for all/most countries) for Sansui T8 20W Bluetooth Speaker.
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)).