Sorry, but no. HPI has gone into receivership, but only Europe. Not america. The HPI savage is a great vehicle, parts will be round for years and years due to their popularity and customer support is still great.
As I previously mentioned, durability is always more important than top speed. Their estimates are inaccurate too- it all depends on the tune of the engine and weather conditions.
$500-$600 is quiet a lot of money for a beginner buggy, and you'll be very pleased with one from the $350-$400 range. Although speed may seem important at first, what you really want is durability and handling in a buggy. Speed also is so greatly affected by tune of the engine and current...