Your request is too general. Help us to try and help you. What brand do you want? Give a comparable product brand, then it might help you in finding a quick solution....Otherwise if you go to alibaba you will find Asian products, with plenty of choice.
Specify things like; Frequency Range/Stability, Maximun Frequency Deviation of Narrow Band Mod, Modulation Signal, Audio input/input level, Maximun Modulation, Non-linearity Distortion, Audio Frequency Response, Power Supply, Cooling Mode, Environment Condition etc. etc.
Am asking these things cos I know someone who is an expert in Microwave technology and they can differentiate between a brand and a cheaper product that will do as good a job (hence me pointing you to Alibaba).
Also, by you being specific on what you want, you avoid telling people "hiyo kaitibu kwanza"!! If you are more specific, it makes it easier to reach a price agreement, you avoid hassling on price and telling someone "hiyo bei juu sana" especially if they do all the hard work to try and find you something only to be rebuffed.