You can maintain your pricelist in a separate private table and delete the original table in FA called #_prices and create a view of your private table called #_prices where # is the table prefix for the company. The fields in the view must match those in the original table:
CREATE TABLE `0_prices` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`stock_id` varchar(20) NOT NULL DEFAULT '',
`sales_type_id` int(11) NOT NULL DEFAULT '0',
`curr_abrev` char(3) NOT NULL DEFAULT '',
`price` double NOT NULL DEFAULT '0',
PRIMARY KEY (`id`),
UNIQUE KEY `price` (`stock_id`,`sales_type_id`,`curr_abrev`)
) ENGINE=MyISAM;
Assuming your private table is called myprices and your company prefix is 1, then your sqls necessary to replace the 1_prices table would be:
DROP TABLE `1_prices`;
CREATE VIEW `1_prices` AS
(SELECT
id AS id,
stock_id AS stock_id,
sales_type_id AS sales_type_id,
curr_abrev AS curr_abrev,
price AS price
FROM myprices);
Alter the above VIEW's sql to suit your private table's actual field names for the source fields but retain the field aliases as it is.