It is possible to create an infinity lava source with a dispenser.
Build a 2 high pipe and place a dispenser on the lower level and place a lava bucket at the top of the pipe. After this put a empty bucket in the dispenser and activate it with a button/lever. After this you take the filled lava bucket and replace it with an empty bucket and do it again...
It's possible to build a lava generator, press the link to see what I mean. (Please don't share the link, the video has a privacy setting, you can watch it only by using this link)

https://youtu.be/u-7NqaxG7Ow