Broadcasting from stream

Hi. I am very new to this "hobby". For some considerable time I have been using a usb fm transmitter to broadcast specialist radio ( vintage stuff ) round my home so that it could be received by all my radios in different rooms. Its a system that has worked brilliantly with no wires and no mess and with a broadcast limit that covers my property. Things have moved on and I cant get a replacement for this item so am looking at alternatives. Does anyone have any suggestions how I can continue to broadcast internet radio to my sets ? I also am able to broadcast to my vintage radio sets via a low powered MW transmitter via a different method. I have been looking at something on Ebay called a Wireless 15W PLL FM Transmitter Radio Stereo Station. I think I can receive the signal via bluetooth to the unite and then broadcast it, but Im not sure. These web sites never tell you what you need to know. Any advice would be appreciated. Best Wishes