Use coupon and get SDR Transceiver Receiver Switch Antenna Sharer TR for $43.99 (from Banggood). You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
Frequency range: DC -160MHz, RF sense threshold: <10mW (1.8MHz-30MHz tested), Size: 126*119*52MM, Insertion loss: < 0.3dB @ 144MHz (0.2dB typical), Maximum TX power: 100W, Power supply: 13.8V DC 200mA, Gas discharge protection, Impedance: 50Ω, RX isolation: > 38dB @ 144MHz (40dB typical), Weight: 430g, ON time: < 20ms / Release time: < 190ms
Latest coupon and price update (UTC):
Banggood ($43.99)
Banggood warehouse is located in China. I’m afraid that there’s no working coupon in Banggood. Well, is it a good price anyway? Pretty good price – average ($47.17) is higher than current one!
Link: Banggood product page
Price: $43.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
There were country-specific coupon codes published on Couponsfromchina social channels and price alerts. Coupon price may vary by country, because there’re different VAT rates, shipping cost etc. There is a chance that some latest coupons are still working:
Old coupons (from the oldest to the newest): COUPONSDE1wk, Cuponation9, BG8ReviTrage, BGcoupon8off, BGGutscheine, BG00c906, ADMITADBLACK, BG8OFFCOUPON, TTBLACK5, BG589b2e, BGSaleFeb8, BG3dabc4, BGa5d988, BGCAPITALOS8, BG881152, BG19c00e
(I don’t think these’re gonna work, but you can try ’em out anyway)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – SDR Transceiver Receiver Switch Antenna Sharer TR [EU] ($-3)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Price history (for all/most countries) for SDR Transceiver Receiver Switch Antenna Sharer TR 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)).