Use a real speedtest like http://speedtest.net and use a wired machine to the modem.
Wifi will drop speeds by 20-30%. Also realize that when you are downloading something the speed is shown in BYTES per second not bits per second. Companies always advertise in bits. There are eight bits in one Byte. So 200kBs is 1600kbs. 600kBs is 4800kbs (or 4.8mbs)
When downloading from a server you will get only the amount of speed the SERVER can deliver which may or may not be anywhere near what your service is capable of delivering. Using different servers will usually return different speeds depending on how loaded the particular server happens to be at the time of the download.
6/7 mbs is SLOW service in most areas at the present time but a few years ago was fast. In the first quarter of 2015, Akamai said, the average U.S. Internet connection speed was 11.9Mbps. Which is nearly twice your ISP's speed. You may want to see if they have a faster package. If you are some distance from the "connection point" you may not be able to get faster service. Our cable service is near 60Mbs/5Mbs upload.
DSL is not near that fast, Fiber may be faster in some locations.
Don't assume you are getting scammed, you probably aren't. Most dsl uploads are still between .5 and 1.5mbs so .3 is slow unless you are on wifi which would convert to that speed in most situations.