There are many online retailers in Norway and throughout Europe. There is one local shop in Stavanger that has kite gear:
Many of the online shops in Norway have sponsored riders in Stavanger that will lend you gear for testing. Ask the shops to arrange a test.
As a Stavanger kiteklubb member, you will get a discount at many of the Norwegian online stores.
Second hand gear
Many of the schools sell off used gear each year.
“SELG DITT SURFBRETT” is a Facebook group for selling surf gear, but often has some kite gear.
Finn.no has a huge amount of second hand kite gear.
Be aware though, there is quite a lot of gear that is either not suited to beginners, or is so old that it is dangerous to fly.
We would not recommend that you buy anything that is older than 4-5 years.
Always ask the seller about damage and repairs to second hand gear.