I know Instabank FX allows scalping. IBFX was somewhat ok with it in the US but the National Futures Assoc is ending hedging and stop/loss signals which is ridiculous. Most brokers don't know you're scalping. Be a modest but consistent trader and you'll be okay.
Here's a list of brokers that allow scalping: >
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I use
Forex4U; so far so good. I did have to reboot 2x as I had delayed trades and heard about some brokers tricks when you get too successful. I just reboot when my trades are closed. I've been told that you should not trade too aggressively i.e. 1:500 when using auto-scalping. That may be true. I'd trade 1:100 or less to be safe.
Go for it.