Crossover / Fuse Repair, Blown Tweeters

My old Optimus PRO LX-10 Tower stopped putting out to the tweeter. I opened up the cabinet and found a "light bulb fuse" (with metal caps on both ends) that was hard-soldered in, and it's blown.
Here's the problem I'm having...
The fuse is a Stanley "27W 12V". I was told it's an automotive courtesy lamp. So, I went to the auto parts store, and they have a ton of similar 12V courtesy lamps, but none are 27V; they are 5V or 10V. I've checked high and low online and can't find it anywhere.
My questions are:
Can I use a different voltage courtesy lamp? Is there a different kind of fuse I can use instead?

Part 2:
I've blown the Linaeum tweeters on my LX10's twice. Is there a different fuse I could use (instead of the one mentioned above)that would blow before the tweeters do?

I realize it's probably user error that blew the tweeters (read: I cranked the stereo too damn high), but I'd still like a little added protection.

Here are the factory specs
Frequency Response: .................... 45-25,000 Hz

Power Handling: ....................... 80 Watts (RMS)

Maximum Power: .................... 160 Watts

Impedance: ................................ 8 Ohms (Nominal)

Speaker Complement: .. 7-inch (17.8 cm) High-Compliance Woofer

2 x 4-inch (5 x 10cm) Wide-Angle Dipole Tweeter

Thanks in advance for your help!