I believe you can also add your custom arrow heads to leaders by creating a block and in ‘dimstyle’ set your block as the new arrow/tick mark

“AutoCAD is Windows only, and won’t work in Ubuntu.” – AutoCAD Support Team
but guess what? you can run AutoCAD in a Virual Machine on Linux, If you are on Ubuntu go ahead and install KVM – Virtual Machine Box

if it’s not yet installed on your system

1) KVM Installation – Follow the tutorial here: https://help.ubuntu.com/community/KVM/VirtManager

2)Installing windows 7 in KVM

3)Install AutoCAD like you normally would on a windows machine.

Other free CAD software on Linux:
There are numerous options, choose the one that you like best.

1. PyCAD
2. Medusa:
   • Download the free software for personal use.
   • Download: medusa4_v4_0_0_linux_personal.sh
   • After downloading the above file, it needs to be marked as executable, so it can be run. To do this, run: chmod +x  filename.sh in a terminal
   • It needs to be executed as root, so use sudo: sudo ./ filename.sh
   • Installation & More information: Here
3. Draftsight
4. Librecad
   • Its already in Ubuntu Repositories.
   • You can get it by running: sudo apt-get install librecad
   • More Information: Librecad
     
5. Let’s not forget Google Sketchup – Built for Architecture work but later expanded it include woodworking and even mechanical solid modeling
6. zwcad – Cost-effective, light-weight and DWG compatible CAD platform; This is the closest CAD software to AutoCAD the runs on LINUX Machines

Hope this helps ?