Which hardware to choose for a Linux server?

Question

linux

Good day dear!
There is a debain 8 server, the following is assigned to its shoulders:
- receive a data stream (via netcat) ~ 1k / sec lines (10 double values ​​in a line)
- process the stream (using python 3)
- write to the database (postgresql 9.5)
What iron to choose? (I suspect that even some small server motherboard can handle it)
* something like: system on SSD, database on HDD.
More specifically:
1) what is the emphasis on, CPU / RAM.
2) how to estimate the size of the HDD (1k lines are written, each line ~ 100bytes )
* how the picture will change if Apache + zabbix is ​​running on it.
Thanks(!)